JP3662184B2 - Liquid phase epitaxial growth method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a liquid phase epitaxial growth method that deposits a solute of a solution on a crystal substrate by applying a temperature difference to the solution, and relates to a liquid phase epitaxial growth method and apparatus capable of improving the uniformity of a wafer growth film thickness. .
[0002]
[Prior art]
  When a low-melting-point metal such as Ga is used as a solvent and GaAs and GaP are used as solutes, a temperature difference is made. When a raw material crystal is placed on the high temperature side and a crystal substrate is placed on the low temperature side, the difference in saturation solubility in the solution The thermal energy causes the crystal material to diffuse toward the low temperature side. Conventionally, there is a liquid phase epitaxial growth method in which crystal growth on a crystal substrate is performed by utilizing diffusion of this crystal material. In this epitaxial growth method, a cooling medium such as a gas is used to effectively make a temperature difference in the solution, and there is a case where heat is absorbed on the low temperature side (crystal substrate side).
[0003]
  In particular, in a horizontal electric furnace, when a temperature difference is made in the vertical direction of a solution, the heaters for the solution can be divided into upper and lower parts, and the upper and lower heaters can be set at different temperatures. However, a temperature difference sufficient by itself cannot be obtained, and it is necessary to absorb heat at the lower side of the solution by forced cooling.
[0004]
  Hereinafter, description will be made by taking GaAs which is a III-V group compound as an example.
[0005]
  In the liquid phase epitaxial growth method utilizing the temperature difference in the solution, the GaAs substrate is set on the substrate support of the boat, and Ga as a solvent containing a dopant and GaAs polycrystal as a solute (raw crystal) are boated. And a soaking plate is disposed above the GaAs polycrystal. Then, the boat is put into a furnace core tube in a hydrogen gas atmosphere, and the temperature of the substrate is raised to 600 to 800 ° C.₂Endothermic with a cooling medium such as gas. In this state, when the saturated solution is brought into contact with the upper surface of the GaAs substrate, crystal growth is performed on the GaAs substrate by material diffusion accompanying the temperature difference of the saturated solution. The reason for installing the soaking plate on the boat is that if the surface of the plate-shaped raw material crystal that is floated on the liquid surface of the solution is a reflecting surface by etching before setting on the boat, the soaking plate is This is because, if not installed on the boat, there is a possibility that the solution will be subject to variation in how to receive the lateral heat from above.
[0006]
  4A and 4B show a cross section of a liquid phase epitaxial growth apparatus that performs epitaxial growth using a temperature difference in a solution using a horizontal growth furnace in which a cooling unit is provided at the lower part of the furnace core tube.
[0007]
  As shown in FIG. 4A, a slide boat 41 is used in the liquid phase epitaxial growth method using the liquid phase epitaxial growth apparatus. According to this sliding boat (hereinafter simply referred to as a boat) 41, a solution reservoir 46 having a solution tank 45 slides relatively on a semiconductor substrate 42 set in a lateral direction on a substrate support 43. Thus, the solution 44 in the solution tank 45 is covered or wiped on the semiconductor substrate 42. The solution 44 is charged with a plate-shaped raw material crystal 52, and a soaking plate 50 is disposed above the raw material crystal 52. Further, as the material of the boat 41, graphite (graphite) that has been subjected to high purity treatment is used.
[0008]
  The liquid phase epitaxial growth method using the liquid phase epitaxial growth apparatus having the above configuration is performed as follows.
[0009]
  First, the boat 41 in which the semiconductor substrate 42 is set on the substrate support 43 is put into a quartz tube 48 as a furnace core tube. In the hydrogen atmosphere in the quartz tube 48, the temperature of the boat 41 is raised by the heater 49, and the lower part of the quartz tube 48 is cooled by the cooling medium 51. In this state, the solution 44 is held for a predetermined time until it becomes a saturated solution.
[0010]
  Thereafter, as shown in FIG. 4B, the solution holder 46 is operated by the operation rod 47, the solution tank 45 is positioned on the semiconductor substrate 42, and the solution 44 is brought into contact with the surface of the semiconductor substrate 42. Thereby, epitaxial growth is performed, and a crystal grows on the semiconductor substrate 42.
[0011]
[Problems to be solved by the invention]
  By the way, in the liquid phase epitaxial growth method, in order to make the growth film thickness distribution uniform on the surface of the semiconductor substrate 42, the semiconductor substrate 42 has a temperature gradient (temperature difference) in the vertical direction with respect to the surface of the semiconductor substrate 42. Temperature uniformity in a direction parallel to the surface of the substrate 42 (horizontal direction) is required. However, due to the difference between the thermal conductivity of the solution 44 and the thermal conductivity of graphite, which is the material of the boat 41, the amount of heat (heat flow rate) flowing up and down in each part of the boat 41 differs. Since the solution tank 45 uses graphite as a material, the thermal conductivity is higher than that of the solution 44, and the temperature gradient (temperature difference) in the vertical direction is difficult to occur near the inner wall of the solution tank 45. As a result, as shown in FIG. 5, on the surface of the semiconductor substrate 42, the growth rate of the peripheral portion is slower than the central portion due to the thermal conductivity of graphite, which is the material of the solution tank 45, and the growth of the peripheral portion thereof. The film thickness becomes thin. That is, there is a problem that the growth film thickness varies on the surface of the semiconductor substrate 42.
[0012]
  Further, it is preferable that the heat supplied to the boat 41 from above is absorbed by the cooling medium 51 through the soaking plate 50 / the raw material crystal 52 / the solution 44 / the semiconductor substrate 42 / the substrate support 43 in order. For this purpose, it is desirable that the raw material crystal 52 and the soaking plate 50 are in close contact with each other in the horizontal direction. However, since the raw material crystal 52 has a plate shape, the solution 44 actually wraps around between the raw material crystal 52 and the soaking plate 50 as shown in FIG. Moreover, since the solution 44 in which the solvent 44 is a low-melting-point metal has viscosity, there are places where the solution 44 wraps around and places where the solution 44 does not wrap around. Atmospheric gas is present at a location where the solution 44 does not enter between the raw crystal 52 and the soaking plate 50. Such a state is different for each set of the solution 44 in the boat 41. As described above, since the atmospheric gas having a low thermal conductivity partially exists between the raw material crystal 52 and the soaking plate 50, the atmosphere gas is contained in the heat flow from the soaking plate 50 to the solution 44. Becomes a heat resistance, and the horizontal heat distribution becomes non-uniform. As a result, the portion where the solution 44 wraps between the raw material crystal 52 and the soaking plate 50 is more likely to transmit heat from the upper portion than the portion where the atmospheric gas exists. As a result, the temperature increases just below the portion where the solution 44 enters between the raw material crystal 52 and the soaking plate 50, and temperature unevenness is generated on the surface of the semiconductor substrate 42. That is, the temperature differs on the surface of the semiconductor substrate 42, and the growth film thickness varies.
[0013]
  SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid phase epitaxial growth method and apparatus capable of eliminating temperature unevenness on the surface of a semiconductor substrate and making the growth film thickness on the surface uniform.
[0014]
[Means for Solving the Problems]
  In order to achieve the above object, the liquid phase epitaxial growth method of the present invention comprises a solution tank having an opening in the lower portion thereof, which is relatively slid on a horizontally set semiconductor substrate in a reaction furnace. In the liquid phase epitaxial growth method in which a solution in a bath is covered or wiped on the semiconductor substrate, a temperature difference is created in the solution, and crystals are grown on the semiconductor substrate using the temperature difference. The semiconductor substrate is disposed on a facing portion that faces the opening of the solution tank at the bottom surface of the recess that accommodates the semiconductor substrate, and a single crystal of the same material as the semiconductor substrate is formed on the facing portion so as to surround the semiconductor substrate. Polycrystalline dummy members are placedThen, by placing a soaking plate on the surface of the semiconductor substrate on the surface of the semiconductor substrate, a soaking plate having a pointed tip is regularly arranged on the top of the solution, so that the raw crystal that becomes the solute of the solution is soaked. Press the plate to submerge the raw crystal in the solutionIt is characterized by that.
[0015]
  According to the liquid phase epitaxial growth method of the above configuration, since the dummy member is disposed so as to surround the semiconductor substrate, the semiconductor substrate is moved away from the inner wall of the solution bath, and the influence of the heat supplied from the inner wall of the solution bath is applied to the semiconductor substrate. It doesn't reach. As a result, a temperature gradient in the direction perpendicular to the surface of the semiconductor substrate is generated, and the temperature in the direction parallel to the surface of the semiconductor substrate is made uniform, so that the growth film thickness distribution on the surface of the semiconductor substrate is made uniform. Can be achieved.
[0016]
  If there is no dummy member around the semiconductor substrate, the solution around the semiconductor substrate becomes supersaturated, so that the crystal material diffuses from the inner periphery to the center of the solution tank, causing variations in film thickness distribution. It becomes.
  In the liquid phase epitaxial growth method of the present invention, the solution tank having an opening in the lower portion is relatively slid on a horizontally set semiconductor substrate in a reaction furnace, thereby In a liquid phase epitaxial growth method in which a solution is covered or wiped on the semiconductor substrate, a temperature difference is created in the solution, and crystals are grown on the semiconductor substrate using the temperature difference, the semiconductor substrate is accommodated. A single crystal or a polycrystal of the same material as the semiconductor substrate so as to surround the semiconductor substrate on the facing portion on the facing portion facing the opening of the solution bath at the bottom surface of the recess A dummy member made of the above is disposed, and a scallop-shaped lifting prevention member is placed in the solution, so that the raw material crystals that become the solute of the solution are Even with, it is characterized by submerging the raw material crystals in the solution.
[0017]
  The liquid phase epitaxial growth method according to an embodiment of the present invention is characterized in that the semiconductor substrate and the dummy member have substantially the same thickness.
[0018]
  According to the liquid phase epitaxial growth method of the one embodiment of the present invention, it is preferable that the semiconductor substrate and the dummy member have substantially the same thickness in order to eliminate variations in film thickness distribution on the surface of the semiconductor substrate.
[0019]
  Further, in the liquid phase epitaxial growth method of the invention of one embodiment, a solution tank having an opening in the lower part is relatively slid on a horizontally set semiconductor substrate in a reaction furnace, thereby In the liquid phase epitaxial growth method in which the solution is covered or wiped on the semiconductor substrate, a temperature difference is created in the solution, and crystals are grown on the semiconductor substrate using the temperature difference, the solute of the solution and The raw material crystal is submerged in the above solution.
[0020]
  According to the liquid phase epitaxial growth method of the embodiment of the present invention, the raw material crystal is placed in the vertical direction in the solution, that is, the raw material crystal is submerged in the solution, and the raw material crystal is intentionally positioned in the solution. For example, the solution wraps around between the soaking plate disposed above the raw material crystal and the raw material crystal, and there is no void. That is, there is no atmospheric gas between the soaking plate and the raw material crystal. Therefore, the contact state with the solution in the soaking plate is the same in each part, and the heat flow from the soaking plate to the solution is uniform in the horizontal direction. As a result, a temperature gradient in the direction perpendicular to the surface of the semiconductor substrate is generated, and the temperature in the direction parallel to the surface of the semiconductor substrate is made uniform, so that the growth film thickness distribution on the surface of the semiconductor substrate is made uniform. Can be achieved.
[0021]
  The liquid phase epitaxial growth method according to an embodiment of the present invention is characterized in that a temperature difference is given to the solution so that the upper part is hotter than the lower part, and the raw crystal is arranged on the high temperature side of the solution. .
[0022]
  According to the liquid phase epitaxial growth method of the invention of the one embodiment, since the source crystal is arranged on the high temperature side of the solution, the source crystal can be effectively diffused.
[0023]
  Moreover, the liquid phase epitaxial growth method of the invention of one embodiment is characterized in that the solvent of the solution is a low melting point metal.
[0024]
  According to the liquid phase epitaxial growth method of the one embodiment of the present invention, since the solvent of the solution is a low melting point metal, the crystal growth on the semiconductor substrate can be performed satisfactorily.
[0025]
  In the liquid phase epitaxial growth method of the embodiment of the present invention, the low melting point metal is Ga.
[0026]
  According to the liquid phase epitaxial growth method of the embodiment of the present invention, since the low melting point metal is Ga, a III-V compound can be grown on a semiconductor substrate.
[0027]
  In the liquid phase epitaxial growth method of one embodiment of the present invention, the source crystal is GaAs or GaP.
[0028]
  According to the liquid phase epitaxial growth method of the invention of the one embodiment, since the source crystal is GaAs or GaP, a III-V compound can be grown on a semiconductor substrate.
[0029]
  In the liquid phase epitaxial growth apparatus of the present invention, the solution tank having an opening in the lower portion is relatively slid on the horizontally set semiconductor substrate in the reaction furnace, so that the solution in the solution tank is In a liquid phase epitaxial growth apparatus that covers or wipes a semiconductor substrate, creates a temperature difference in the solution, and grows a crystal on the semiconductor substrate using the temperature difference, a recess for housing the semiconductor substrate is provided. Arrangement part for arranging dummy members around the semiconductor substrate on the bottom surfaceAnd a soaking plate arranged on the top of the solution tank and having protrusions with pointed tips regularly formed on the surface,The crystal is grown substantially uniformly on the entire surface of the semiconductor substrate.
[0030]
  According to the liquid phase epitaxial growth apparatus having the above configuration, the semiconductor substrate is a dummy member by arranging the dummy member in the arrangement portion because the arrangement portion for arranging the dummy member is provided around the semiconductor substrate. The semiconductor substrate is surrounded by the inner wall of the solution tank and the influence of the heat supplied from the inner wall of the solution tank does not reach the semiconductor substrate. As a result, a temperature gradient in the direction perpendicular to the surface of the semiconductor substrate is generated, and the temperature in the direction parallel to the surface of the semiconductor substrate is made uniform, so that the growth film thickness distribution on the surface of the semiconductor substrate is made uniform. Can be achieved.
[0031]
[0032]
  AlsoThe soaking plate is arranged in the upper part of the solution tank, so when, for example, a raw material crystal is put into the solution in the solution tank, the raw crystal is uniformly pressed by the protrusions of the soaking plate, and the raw crystal is a solution. Located inside. As a result, the solution flows between the protrusions, and no gap exists between the soaking plate and the raw crystal, so that the contact state with the solution on the soaking plate can be made the same in each part.
[0033]
  Moreover, the liquid phase epitaxial growth apparatus of the present invention comprises:In the reaction furnace, a solution tank having an opening in the lower portion is relatively slid on a horizontally set semiconductor substrate, so that the solution in the solution tank is covered or wiped on the semiconductor substrate. In the liquid phase epitaxial growth apparatus for growing a crystal on the semiconductor substrate by making a temperature difference in the solution, a dummy member is formed around the semiconductor substrate at the bottom surface of the recess for housing the semiconductor substrate. An arrangement part for arrangingA scallop-shaped anti-floating member disposed in the solutionWhenWithSo that the crystal grows substantially uniformly on the entire surface of the semiconductor substrate.It is characterized by that.
[0034]
  the aboveConstitutionAccording to this liquid phase epitaxial growth apparatus, for example, a raw material crystal charged in the solution in the solution tank is submerged under the anti-floating member, and the raw material crystal is positioned in the solution. At this time, since the anti-lifting member has a scallop shape, the solution flows, for example, between the soaking plate and the starting crystal disposed above the starting crystal, and there is a gap between the soaking plate and the starting crystal. Since it does not exist, the contact state with the solution on the soaking plate can be made the same in each part.
[0035]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, the liquid phase epitaxial growth method and apparatus of the present invention will be described in detail with reference to embodiments shown in the drawings.
[0036]
  FIG. 1A shows a schematic cross-sectional view of an epitaxial growth apparatus for performing a liquid phase epitaxial growth method according to an embodiment of the present invention, and FIG. 1B shows a schematic cross-sectional view of the main part of the liquid phase epitaxial growth apparatus. Show. 1A and 1B show a state in which the opening 15 of the solution tank 5 provided in the solution reservoir 6 of the boat 1 and the recess 13 of the substrate support 3 of the boat 1 are opposed to each other. Yes.
[0037]
  As shown in FIG. 1A, the liquid phase epitaxial growth apparatus includes a quartz tube 8 as a reaction furnace, a heater 9 for heating the quartz tube 8, and a sliding boat (hereinafter referred to as a sliding boat) accommodated in the quartz tube 8. , Simply say a boat). The boat 1 includes a substrate support 3 provided with a recess 13 for accommodating a semiconductor substrate 2, and a solution reservoir 6 that is placed on the substrate support 3 and slides relative to the substrate support 3. And have. The solution reservoir 6 slides relatively on the substrate support 3 to cover or wipe the semiconductor substrate 2 with the solution 4 in the solution tank 5 formed in the solution reservoir 6. Note that hydrogen gas is supplied into the quartz tube 8 from a supply port (not shown). Further, heat absorption at the lower part of the quartz tube 8 is performed by the cooling medium 11.
[0038]
  Further, as shown in FIG. 1B, the bottom area of the recess 13 of the substrate support 3 and the opening area of the solution tank 5 are equal to each other, and the opposite of the recess 13 facing the opening 15 of the solution tank 5. The semiconductor substrate 2 is disposed on the bottom surface 13a as a part. When a III-V compound is grown on the semiconductor substrate 2, for example, a low melting point metal such as Ga can be used as the solvent of the solution 4. For example, GaAs or GaP can be used as the source crystal 12 that becomes the solute of the solution 4. Can be used. The raw material crystal 12 is located above the solution 4. Further, a soaking plate 10 is disposed above the raw material crystal 12, that is, above the solution tank 5, and a conical protrusion 20 having a sharp tip is formed on the surface of the soaking plate 10 on the raw crystal side. Are regularly formed. An arrangement portion 23 for arranging the dummy member 18 is provided around the semiconductor substrate 2 on the bottom surface 13 a of the recess 13. As shown in FIG. 2, there are four dummy members 18 and are arranged in the arrangement portion 23 so as to surround the semiconductor substrate 2. There is no substantial gap between the dummy members 18, and the dummy members 18 substantially continuously surround the semiconductor substrate 2. The dummy member 18 is made of a single crystal of the same material as the semiconductor substrate 2.
[0039]
  In the liquid phase epitaxial growth method using the liquid phase epitaxial growth apparatus having the above configuration, the semiconductor substrate 2 is set horizontally in the recess 13 of the substrate support 3 and the solution tank 5 is filled with the solution 4 containing the raw crystal 12. A soaking plate 10 is disposed on the raw crystal 12. Then, the boat 1 is put in a quartz tube 8 in a hydrogen atmosphere and heated up to a predetermined substrate temperature, and heat is absorbed by the cooling medium 11 at the lower part of the quartz tube 8. As a result, the upper portion of the solution 4 is heated to a higher temperature than the lower portion, and the raw crystal 12 is positioned on the high temperature side of the solution 4. Thereafter, when the operation rod (not shown) is operated to slide the solution reservoir 6 relative to the substrate support 3 to bring the saturated solution 4 into contact with the upper surface of the semiconductor substrate 2, the saturated solution 4 is obtained. With the temperature difference, the solute diffuses and crystals grow on the semiconductor substrate 2. At this time, since the concave member 13 is disposed so as to surround the semiconductor substrate 2, the semiconductor substrate 2 is moved away from the inner wall of the solution tank 5, and the influence of heat supplied from the inner wall of the solution tank 5. Does not reach the semiconductor substrate 2. As a result, a temperature gradient in the direction perpendicular to the surface of the semiconductor substrate 2 occurs, and the temperature in the direction parallel to the surface of the semiconductor substrate 2 becomes uniform. As shown in FIG. Uniformity of the growth film thickness distribution on the surface can be achieved.
[0040]
  Further, since the placement portion 23 for placing the dummy member 18 is provided around the semiconductor substrate 2 on the bottom surface 13a of the recess 13, the semiconductor substrate 2 is disposed by placing the dummy member 18 in the placement portion 23. Can be surrounded by a dummy member 18.
[0041]
  Moreover, it is preferable that the semiconductor substrate 2 and the dummy member 18 have substantially the same thickness in order to eliminate variations in film thickness distribution on the surface of the semiconductor substrate 2.
[0042]
  Further, since the soaking plate 10 is arranged on the upper part of the solution tank 5, the raw material crystals 12 in the solution 4 of the solution bath 5 are uniformly pressed by the protrusions 20 of the soaking plate 10, so that the raw crystal 12 is Located in solution 4. That is, the raw material crystal 12 sinks and is located in the solution 4. As a result, the solution 4 wraps around between the protrusions 20, and no gap exists between the soaking plate 10 and the raw crystal 12, and the contact state with the solution 4 on the soaking plate 10 becomes the same in each part. Thus, the heat flow from the soaking plate 10 to the solution 4 becomes uniform in the horizontal direction. As a result, the temperature in the direction parallel to the surface of the semiconductor substrate 2 becomes more uniform while having a temperature gradient in the direction perpendicular to the surface of the semiconductor substrate 2, so that a growth film on the surface of the semiconductor substrate 2 is formed. It can be made more uniform.
[0043]
  In addition, since the raw material crystal 12 is disposed above the solution 4, that is, on the high temperature side, the raw material crystal 12 can be effectively diffused.
[0044]
  In the above embodiment, the heater 9 is not divided into upper and lower parts, but may be divided. The quartz tube 8 may be a vertical type or a horizontal type.
[0045]
  In the above embodiment, the dummy member 18 is made of a single crystal of the same material as the semiconductor substrate 2, but may be made of polycrystal.
[0046]
  The number of the dummy members 18 is four, but may be one, for example. In this case, by arranging an annular dummy member so as to surround the semiconductor substrate 2, the same effects as in the present embodiment can be obtained. In short, the number of the dummy members is not particularly limited.
[0047]
  In addition, the dummy members 18 are arranged substantially continuously so as to surround the semiconductor substrate 2 without providing a gap between the dummy members 18, but the semiconductor substrate 2 is formed without providing a gap between the dummy members. You may arrange | position a dummy member continuously so that it may surround. Further, a gap may be provided between the dummy members, and the dummy members may be discontinuously arranged around the semiconductor substrate 2.
[0048]
  Moreover, in the said embodiment, although the bottom area of the recessed part 13 and the opening area of the solution tank 5 were equal, it does not need to be equal, for example, the bottom area of a recessed part becomes larger than the opening area of a solution tank. It may be.
[0049]
  Moreover, in the said embodiment, although the processus | protrusion 20 of the soaking | uniform-heating plate 10 was conical shape, shapes, such as a triangular pyramid and a quadrangular pyramid, may be sufficient, for example.
[0050]
  FIG. 3 is a cross-sectional view of a main part in a liquid phase epitaxial growth apparatus according to another embodiment of the present invention. Note that the same members as those in FIG. According to this liquid phase epitaxial growth apparatus, as shown in FIG. 3, a soaking plate 30 having a smooth surface on the source crystal 12 side is used instead of the soaking plate 10 (see FIG. 1), and the solution bath 5 A slat-shaped lifting prevention member 39 is arranged in the solution 4. The raw material crystal 12 is submerged under the anti-lifting member 39 so that the raw material crystal 12 is positioned in the solution 4. At this time, since the lifting prevention member 39 has a scallop shape, the solution 4 flows between the soaking plate 30 and the raw material crystal 12, and no gap exists between the soaking plate 30 and the raw crystal 12. Thus, the contact state of the soaking plate 10 with the solution 4 can be made the same in each part, and the same effect as the present embodiment can be obtained.
[0051]
【The invention's effect】
  As described above, in the liquid phase epitaxial growth method of the present invention, since the dummy member is disposed so as to surround the semiconductor substrate, the semiconductor substrate is moved away from the inner wall of the solution tank, and a temperature gradient in a direction perpendicular to the surface of the semiconductor substrate is generated. The temperature in the direction parallel to the surface of the semiconductor substrate becomes uniform, and the growth film thickness distribution on the surface of the semiconductor substrate can be made uniform.
[0052]
  In the liquid phase epitaxial growth method according to an embodiment of the present invention, it is preferable that the semiconductor substrate and the dummy member have substantially the same thickness in order to eliminate variations in film thickness distribution on the surface of the semiconductor substrate.
[0053]
  In the liquid phase epitaxial growth method of the invention of one embodiment, since the source crystal is submerged in the solution and the source crystal is intentionally positioned in the solution, for example, the soaking plate disposed above the source crystal and the source crystal There is no gap between them, and the contact state with the solution in the soaking plate is the same in each part, and the heat flow from the soaking plate to the solution is uniform in the horizontal direction. As a result, a temperature gradient in the direction perpendicular to the surface of the semiconductor substrate is generated, and the temperature in the direction parallel to the surface of the semiconductor substrate becomes uniform, so that the growth film thickness distribution on the surface of the semiconductor substrate is made uniform. Can be achieved.
[0054]
  In the liquid phase epitaxial growth method according to one embodiment of the present invention, since the raw material crystal is arranged on the high temperature side of the solution, the raw material crystal can be effectively diffused.
[0055]
  According to the liquid phase epitaxial growth method of an embodiment of the present invention, the solvent of the solution is a low melting point metal, so that the crystal growth on the semiconductor substrate can be favorably performed.
[0056]
  According to the liquid phase epitaxial growth method of an embodiment of the present invention, since the low melting point metal is Ga, a III-V compound can be grown on a semiconductor substrate.
[0057]
  According to the liquid phase epitaxial growth method of an embodiment of the present invention, since the source crystal is GaAs or GaP, a III-V compound can be grown on a semiconductor substrate.
[0058]
  Moreover, since the liquid phase epitaxial growth apparatus of this invention is equipped with the arrangement | positioning part for arrange | positioning a dummy member around the said semiconductor substrate, it arrange | positions with respect to the surface of a semiconductor substrate by arrange | positioning a dummy member in the arrangement | positioning part. As a result, a temperature gradient in the vertical direction occurs, and the temperature in the direction parallel to the surface of the semiconductor substrate becomes uniform, so that a uniform growth film thickness distribution on the surface of the semiconductor substrate can be achieved.
[0059]
  In the liquid phase epitaxial growth apparatus according to an embodiment of the present invention, since the soaking plate is disposed in the upper part of the solution tank, for example, when starting material crystals are put into the solution in the solution tank, the starting crystals are protrusions of the soaking plate. The raw material crystals are located in the solution and the contact state with the solution on the soaking plate can be made the same in each part.
[0060]
  In the liquid phase epitaxial growth apparatus according to the embodiment of the present invention, the scallop-shaped lifting prevention member is arranged in the solution, so that the solution is placed between, for example, the soaking plate and the raw material crystal arranged above the raw crystal. As a result, there is no gap between the soaking plate and the raw material crystal, and the contact state with the solution on the soaking plate can be made the same in each part.
[Brief description of the drawings]
FIG. 1A is a schematic cross-sectional view of a liquid phase epitaxial growth apparatus according to an embodiment of the present invention, and FIG. 1B is an enlarged cross-sectional view of the main part of the liquid phase epitaxial growth apparatus.
FIG. 2 is a top view of a growth area of the liquid phase epitaxial growth apparatus and a graph showing a thickness distribution of a semiconductor substrate in the growth area.
FIG. 3 is an enlarged cross-sectional view of a main part of a liquid phase epitaxial growth apparatus according to another embodiment of the present invention.
FIG. 4 is a cross-sectional view of a conventional liquid phase epitaxial growth apparatus.
FIG. 5 is a schematic sectional view of the conventional liquid phase epitaxial growth apparatus, a top view of a growth area of the conventional liquid phase epitaxial growth apparatus, and a graph showing a thickness distribution of a semiconductor substrate in the growth area.
FIG. 6 is an enlarged cross-sectional view of a main part of the conventional liquid phase epitaxial growth apparatus.
[Explanation of symbols]
2 Semiconductor substrate
5 Solution tank
8 Quartz tube
13 recess
13a Bottom of recess
15 opening
18 Dummy material

Claims (9)

In the reaction furnace, a solution tank having an opening in the lower portion is relatively slid on a horizontally set semiconductor substrate, so that the solution in the solution tank is covered or wiped on the semiconductor substrate. In the liquid phase epitaxial growth method of adding a temperature difference to the solution and growing a crystal on the semiconductor substrate using the temperature difference,
The semiconductor substrate is disposed on a facing portion facing the opening of the solution tank at the bottom surface of the concave portion that accommodates the semiconductor substrate,
A dummy member made of a single crystal or a polycrystal of the same material as the semiconductor substrate is disposed on the facing portion so as to surround the semiconductor substrate ,
On the top of the solution, by placing a soaking plate with regularly pointed protrusions formed on the surface of the semiconductor substrate, the raw crystal that becomes the solute of the solution is placed on the soaking plate. A liquid phase epitaxial growth method, characterized in that the raw material crystal is submerged in the solution by pressing . In the reaction furnace, a solution tank having an opening in the lower portion is relatively slid on a horizontally set semiconductor substrate, so that the solution in the solution tank is covered or wiped on the semiconductor substrate. In the liquid phase epitaxial growth method of adding a temperature difference to the solution and growing a crystal on the semiconductor substrate using the temperature difference ,
The semiconductor substrate is disposed on a facing portion facing the opening of the solution tank at the bottom surface of the concave portion that accommodates the semiconductor substrate,
A dummy member made of a single crystal or a polycrystal of the same material as the semiconductor substrate is disposed on the facing portion so as to surround the semiconductor substrate,
To the above solution in, by arranging the uplift preventing member gridiron shape, the raw crystal comprising a solute of the solution are pressed by preventing member Ri said levitation, characterized Rukoto submerged the raw material crystals in the solution Liquid phase epitaxial growth method. In the liquid phase epitaxial growth method according to claim 1 or 2 ,
Liquid phase epitaxial growth method in which the semiconductor substrate and the said dummy member is substantially characterized the same thickness der Rukoto. In the liquid phase epitaxial growth method according to any one of claims 1 to 3,
A liquid phase epitaxial growth method characterized in that a temperature difference is given to the solution so that the upper part is hotter than the lower part, and the raw crystal is arranged on the high temperature side of the solution. In the liquid phase epitaxial growth method according to any one of claims 1 to 4,
A liquid phase epitaxial growth method, wherein the solvent of the solution is a low melting point metal. In the liquid phase epitaxial growth method of Claim 5,
The liquid phase epitaxial growth method, wherein the low melting point metal is Ga. In the liquid phase epitaxial growth method according to any one of claims 1 to 6,
A liquid phase epitaxial growth method, wherein the source crystal is GaAs or GaP. In the reaction furnace, a solution tank having an opening in the lower portion is relatively slid on a horizontally set semiconductor substrate, so that the solution in the solution tank is covered or wiped on the semiconductor substrate. In the liquid phase epitaxial growth apparatus for adding a temperature difference to the solution and growing a crystal on the semiconductor substrate using the temperature difference,
An arrangement portion for arranging a dummy member around the semiconductor substrate on the bottom surface of the recess for housing the semiconductor substrate ;
A soaking plate disposed on the top of the solution tank and having protrusions with pointed tips regularly formed on the surface ;
A liquid phase epitaxial growth apparatus characterized in that crystals are grown substantially uniformly on the entire surface of the semiconductor substrate. In the reaction furnace, a solution tank having an opening in the lower portion is relatively slid on a horizontally set semiconductor substrate, so that the solution in the solution tank is covered or wiped on the semiconductor substrate. In the liquid phase epitaxial growth apparatus for adding a temperature difference to the solution and growing a crystal on the semiconductor substrate using the temperature difference ,
An arrangement portion for arranging a dummy member around the semiconductor substrate on the bottom surface of the recess for housing the semiconductor substrate;
Includes a <br/> and uplift preventing member gridiron shape arranged above solution in,
A liquid phase epitaxial growth apparatus characterized in that crystals are grown substantially uniformly on the entire surface of the semiconductor substrate .

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